POS0036 SUBSEQUENT HOSPITALIZATIONS FOR OR WITH PSYCHIATRIC DISORDERS IN INDIVIDUALS WITH PRE-EXISTING RHEUMATOID ARTHRITIS AND SPONDYLARTHRITIS: A NATIONAL REGISTRY-BASED RETROSPECTIVE COHORT STUDY
Authors: T. Formanek, K. Mladá, P. Mohr, M. Olejárova, K. Pavelka, M. Husakova
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> The crosslink between rheumatic diseases (RD) and psychiatric disorders (PD) has been suggested, particularly due to systemic inflammation and the psycho-social impact of chronic painful experience in patients with RD. <h3>Objectives</h3> In the present study, we investigated the risk of subsequent hospitalization (1) for PD and (2) either for or with PD in cohorts of patients with specific pre-existing RD. <h3>Methods</h3> In this retrospective cohort study, we utilized data from the Czech nation-wide registers of all-cause hospitalizations and deaths. The study consisted of individuals first hospitalized with (1) rheumatoid arthritis (RA; International Classification of Diseases 10th Revision (ICD-10) codes M05 and M06) and (2) spondylarthritis (SpA; ICD-10 codes M07, M45 and M46[1, 8, 9]) in the time-period from 1999 to 2011 (index hospitalization) and counterparts without the respective diseases, exactly matched on age, sex, month and year at the index hospitalization (1:5). The risk of subsequent hospitalization (1) for and (2) either for or with each diagnostic group of PD (ICD-10 codes F0x + G20 and G30, F1x, F2x, F3x, F4x and F5x) arising in the period of five or more years (up to 2017) from the index hospitalization was assessed using stratified Cox proportional hazards models, controlling for deaths occurring in this time-period and adjusting for age, sex and month and year at the index hospitalization. We assessed the risk (1) of being hospitalized for PD (ie, primary diagnosis) and (2) of being hospitalized for or with PD (ie, either primary or secondary diagnosis) separately. For the respective analyses, we excluded individuals who were (1) hospitalized for PD and (2) hospitalized either for or with PD five or more years (up to 1994) prior to the index hospitalization, separately for each diagnostic group of PD. Thus, we effectively created 24 matched cohorts overall. The results are expressed as hazard ratios (HR) with 95% confidence intervals (95% CI). <h3>Results</h3> When considering hospitalizations specifically for PD, the total number of individuals in the RA cohorts ranged from 92,694 to 93,768 and from 31,488 to 32,088 individuals in the SpA cohorts, whereas when considering hospitalizations either for or with PD, the number of individuals in the RA cohorts ranged from 91,290 to 93,726 and from 30,852 to 32,070 individuals in the SpA cohorts. We found that individuals with SpA had an elevated risk of hospitalization for anxiety disorders (1.36; 1.08 to 1.70), when compared with matched counterparts. Conversely, we found that individuals with RA had a decreased risk of hospitalization for substance use disorders (0.58; 0.46 to 0.72). Next, we found that individuals with RA and SpA had an elevated risk of being hospitalized either for or with mood disorders (1.18; 1.06 to 1.31 and 1.26; 1.02 to 1.54) and anxiety disorders (1.24; 1.12 to 1.36 and 1.32; 1.11 to 1.56). In addition to this, people with RA had a higher risk of being hospitalized either for or with organic PD (1.25; 1.16 to 1.35) and people with SpA demonstrated an increased risk for hospitalization listing behavioral syndromes associated with physiological disturbances and physical factors as one of the diagnosis (2.73; 1.59 to 4.71). Conversely, people with RA had a lower risk of being hospitalized either for or with substance use disorders (0.77; 0.68 to 0.87). For the other PD outcomes in people with RA and SpA, the 95% CIs covered a range from decreased to increased risk. <h3>Conclusion</h3> Individuals with RA and SpA seem to have a higher risk of developing a range of PD, when compared with matched counterparts. The detected differences suggest that clinical vigilance and provision of mental health services to affected individuals require further attention. <h3>Acknowledgements</h3> This work was supported by the Czech Health Research Council (NU21-09-00297) and by the National Institute for Health Research, Applied Research Collaboration, East of England (TF). <h3>Disclosure of Interests</h3> None Declared.